Automatic controller



E. THOMPSON AND C. W. JAMESON.

AUTOMATIC CONTROLLER. APPLICATION FILED APR. 7. m7.

Patented June 10, 1919.

UNITED snares PATENT curios.

JOHN E. THOMPSON fiI lL QLAli-ENCE XV. JAMESON, OF CHICAGO, ILLINOIS, ASSIGNORS. BY MESNE ASSIGNMENTS, Ti ATLAS ELECTRIC DEVICES $0., A (.JGRPORfiTION OF ILLINOIS.

AUEGMATIC CONTROLLER.

eoceoe.

Specification of Letters Patent.

Patented June 10, 1919.

ment in Automatic Controliers,-=-of which the I following is a specification,

Our invention relates to lli'lPIlOTBTIlG-HllS in automatic controller switches, more particularly of the type ada )tGCl for varying the resistance in the circuits of electric motors.

Our object is to provide an improved switch of this character which will be showing several of the yieldable contacts carried thereby;

Fig. 3 isa sectional detail through one of the contacts, this View being talien'on line 33 of Fig. 2;

Fig. 1 is an enlarged detail in plan, of one of the fixed contacts.

The structure which we have shown in the drawings am which embodies our invention, is designed more particularly tor use in connection with the starting or accelerating of electric elevator motors. This switch is ar'angcd to automaticall} vary the resistance in the circuit which includes the motor,- all in the manner which 'is well konwn to those skilled in the art. Hence, a description of the circuits in which the switch is intended to be associated, is deemed unnecessary. However, our improved switch is capable of being associated in a circuit such. as; we ha vc. shown and described in our CU-pOlHl'lllg application, Serial No. 430,144. tiled November 1, 19153. The structux-c which we have shown in the drawings tunbodlcs suitable supporting board or panel A of suitable insulating material upon which the various parts are mounted .in'" their proper relation. Outstanding from the panel is a plurality of fixed contacts ll which are carried in suitable brackets C rigidly mounted upon the panel.

As showniii Figs. 1 and 4, these contacts comprise cylindrical members which are preferably niade'of carbon or any other suitable n'iateri'a'l forth'e purpose. The brackets C are provided'with integral split rings at their outer ends, in which the carbon contacts are clamped. :flhe portions of this ring are clamped by means of the screws C which permitsof removal or adjustment of said contacts. The contacts are, in this. structure, positioned in a substantially horizontal row and equally spaced apart. The lower or contact faces 13 of these contacts I are flat and are all positioned in substantially the same horizontal plane. Cooperating with these fixed contacts is a plurality of movable contact members D which in this case are similar in construction and material to the. contact mcmhcrs B. The contact members D have similar flat contact faces or ends D which are preferably positioned in substantially the same plane, but this plane is disposed at an angle to the plane which the contact faces ll occupy, so that the contacts D may be successively brought into and out of engagement with the fixed contacts B. The contact members I) are all carried in a swinging arm or bar E which is pivoted at one end IQ upon the supporting panel A at such an angzlc lo the plane of contacts ll that whcnswung about its pivot the bar or arm carries the contacts D into successiveengagement with the fixed contacts 13. Hence this movable arm normally occupies a position at, such an angle that it will normally maintain the plane of the Contact laces D at the proporf angle with respect to they plane of the contact faces B. The other end 1? ol' the arm d) isi'orked to embrace the core cktbnsion l of an actuating solenoid F It is connected to this extension by means of a pivot bolt F which extends through the extension l and operates in slots F in the "forks of said movable arm E. This cmistruction permits of a relative movement between lho arm 1C and the extension. as the solenoid operates to swing the arm l1 about its pivot. 'lho opcrating solenoid F may be of any suitable Ill?) construct-ion used in switches of this char- I acter, and it may be energized in the usual manner to cause it to swing the arm E about its pivot. The lower end of the core extension carries a piston F which operates within a cylinder F mounted upon the panel, which constructi-ui constitutes a suitable dash-pot for regulating the pull of the solenoid. Tlu= pivoted arm E is preferably formed as a'fiat strip or plate having downwardly'depending flanges or ribs E at its edges for strength, thus enabling a comparatively light arm to be used for this purpose. The contacts D, as hereinbefore mentioned, are cylindrical in form and are positioned to slide freely within suitable openings in the arm E, these openings being surrounded by integral upstanding flanges E to provide suitable guide bearings for the contact members. Each of the contact members D is individually supported in a cup-shaped member G carried on the under side of the arm F. Each cup-shaped member G has upstanding extensions G the upper ends G of which are turned horizontally and provided .with openings through which the rods Gt pass so that the cup members which support the contacts may slide on the rods Gr toward and from the arm E. The guide rods G are supported in a. depending position from the arm E. They pass through holes or lopenings G in said arm. At their upper ends these rods have washers G which are held by cotter pins The lower ends of the rods are likewise. provided with washers (l and cotter pins G The cupshaped inembers (lr are yieldingly held in position against the under sideot' the arm i l) by means of spiral springs G which surround the rods (l and which are positioned between the extensions (l and the lower washers (i \Vhcn the contact members D, however, are pressed into engagement with the fixed contact members, the springs G yield and the contacts move downwardly in the bearings l carrying the cup-shaped members (i with them. Each contact is thus yieldingly held in engagement with its corresponding fixed contact. It. will be noted that because. ol the angularity ot' position-oi the conlacls the corresponding contacts of each series are normally out of alinemcnt. Hence when the contacts l) are moved into and out of alincmcnt with contacts 1% their contact 'laces move relatively laterally with a rubbing action which operates to clean the Contact surfaces and grind them into perfect contact. It will also be noted the holes in the arm E and in the cup extensions G through which the rods G pass are comparatively larger than the rods and that the contacts D are loosely held in the cups G. This construction permits considerable free movement of these parts which prevents the parts from binding and thus insuring their proper operation at all times. Furthermore, the parts are all readily renewable when worn or damaged, and are inexpensive since no machine work is necessary either in the manufacture or assembling of the parts. Theentire structure is simple and its re peated operation is reliable and effective. The arm E is intended as a current carrying member and in order to provide a substantial and effective electrical connection 'between the contacts and the arm the contacts I) have flexible cable pigtails G iastened at one end directly to the carbons and at their other ends directly to the arm, both connec tions being made lVe claim:

The combination of a supporting panel, a. plurality of brackets outstanding from the face of the panel, carbon contact blocks mounted in said brackets and arranged with their contact faces in the same plane, a bar pivoted at one end on said supporting panel and normally arranged at an angle to the said contact faces and to move toward said fixed contacts into parallel. relation thereto, a plurality of contact bearings in said arm, a plurality of contact blocks movable in said bearings with their contact faces normally arranged ina plane at an angle to the plane of the contact faces of said fixed contactsso that when the bar is swung about its pivot said yielding cont-acts will successively engage the fixed contacts, and individual spring-pressed supports on the underside of said bar arranged-t0 yield as the contacts are successively brought into contact. A

Signed by us at Chicago, Illinois, this 27 day of March, 1917.

JOHN ll. THOMPSON-i (lIn-XRENUE JAMESUN. 'itncsscs:

E. ii. Ounce, ELLA Tnmnn.

by suitable screws. 

